The invention relates to a switching device according to the preamble of the independent claim.
Switching devices are instruments employed for opening and closing an electric circuit. The switching device comprises at least one pole and a control device adapted to open and close said pole. Switching devices include switches and switch-fuses, for example.
Switching devices have a 0 position, wherein the poles of the switching device are open, and an I position, wherein the poles of the switching device are closed. The positions of the poles of the switching device are changed by rotating the main shaft of the switching device. For rotating the main shaft, switching devices are provided with an actuator having a 0 position and an I position, which correspond to the 0 position and I position of the switching device.
Some switching devices also have a testing position, wherein the poles of the switching device are open, but the position of the auxiliary contacts corresponds to the I position of the switching device.
The problem in known switching devices is to accomplish the testing position. In some known switching devices, separate lever mechanisms are used to accomplish the testing position, but such an assembly is complex.